A serum assay is rather imprecise. The results of repeated assays of a single specimen follow a normal distribution with mean equal to the serum concentration for that specimen and a std dev=4 U/Li. A lab measures many specimens daily, and specimens w/ reported values of 40 or more are flagged "unusually high." If a patient's true concentration is 35 U/Li, find probability that their specimen will be flagged "unusually high" if the reported value is the result of a single assay.

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